<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .father {
            width: 300px;
            height: 300px;
            background-color: pink;
            /* padding-top: 50px; */
            /* border: 1px solid #000; 若设计稿没有边框线 ，则不能用此方法*/
            overflow: hidden; 
        }
        .son {
            width: 100px;
            height: 100px;
            background-color: skyblue; 
            margin-top: 50px;
        }
    </style>
</head>
<body>
    <div class="father">
        <div class="son">son</div>

    </div>
</body>
</html>